Female Repro

Question 1

What are the 5 stages of folliculogenesis?

Answer 1

Primordial > primary > secondary > antral > pre-ovulatory

Question 2

Describe the morphology of a primordial follicle?

Answer 2

Primary oocyte + single layer of squamous follicular cells

Question 3

Describe the morphology of a primary follicle?

Answer 3

Primary oocyte + single layer of cuboidal follicular cells

Question 4

Describe the morphology of a secondary follicle?

Answer 4

Primary oocyte with 2-6 layers of follicular cells. ZP begins developing

Question 5

Describe the morphology of an antral (tertiary) follicle?

Answer 5

6+ layers of follicular cells, and a fluid-filled antrum is present. ZP fully developed

Question 6

Describe the morphology of a preovulatory (graafian) follicle?

Answer 6

Similar to antral - corona radiata surrounds oocyte/ZP, then antrum, then membrana granulosa

Question 7

What is the cumulus oophorus?

Answer 7

Thickened mound of granulosa cells that surround the oocyte and project into the antrum

Question 8

What are the main differences between the theca interna and theca externa?

Answer 8

I - cells are endocrine-like and border the membrana granulosa
E - fibroblast-like cells outside the theca interna; not discernible under light microscopy (blends with stroma)

Question 9

Briefly describe the process of follicular regression?

Answer 9

Active cellular process - infiltration of macrophages, phagocytosis, migration of fibroblasts from theca externa, and production of collagen

Question 10

When does the primary oocyte complete its first meiotic division?

Answer 10

Immediately before ovulation (in response to LH surge) - forms secondary oocyte

Question 11

What is the corpus hemorrhagicum?

Answer 11

After a Graafian follicle ovulates, blood from torn blood vessels of the theca interna invades the collapsed follicle

Question 12

Describe the process of lutenization?

Answer 12

Remaining granulosa and theca interna cells undergo hypertrophy, proliferate, and invade corpus hemorrhagicum

Question 13

What is the corpus albicans?

Answer 13

Degenerated corpus luteum - connective tissue has replaced luteal cells

Question 14

How many follicular waves in a bovine estrus cycle?

Answer 14

2-3

Question 15

What are the two brain centres controlling GnRH release?

Answer 15

Tonic centre and surge centre

Question 16

How does GnRH release differ between tonic and surge centers?

Answer 16

Tonic - Spontaneous, low level, and constant
Surge - Induced by E, high level, sporadic

Question 17

What causes activation of the surge centre for GnRH release?

Answer 17

Estrogen production by growing antral follicles

Question 18

What hormone is responsible for promoting the emergence of a follicular wave?

Answer 18

FSH

Question 19

How does hormone dependence of follicles change during the Selection process of a follicular wave?

Answer 19

Dependence of dominant follicle switches from FSH to LH

Question 20

How is the “dominant follicle” defined?

Answer 20

Largest follicle in a wave

Question 21

What is the hormonal process behind ovulation of the dominant follicle?

Answer 21

Estradiol from dominant follicle changes from negative to positive feedback on the anterior pituitary, resulting in an LH surge

Question 22

What is the main hormone produced by the corpus luteum?

Answer 22

Progesterone

Question 23

How does progesterone act on the hypothalamus/pituitary?

Answer 23

Negative feedback

Question 24

How does the corpus luteum interact with other growing follicles?

Answer 24

Suppresses growth by preventing estradiol-induced LH surge

Question 25

What hormone stimulates luteolysis and what tissue produces it?

Answer 25

Prostaglandin F2a produced by the endometrium

Question 26

What is the hormonal cause of pseudopregnancy in dogs?

Answer 26

Progesterone - P4 profile similar in pregnant and non-pregnant dogs

Question 27

What are the main follicular/hormonal changes associated with reproductive senescence?

Answer 27

Fewer follicles at wave emergence, CL smaller, P4 levels lower

Question 28

What are the two main phases of the estrous cycle?

Answer 28

Luteal and follicular (between CL regression and ovulation)

Question 29

What are the primary hormones during the luteal and follicular phases of the estrous cycle?

Answer 29

Luteal - Progesterone Follicular - estrogen (estradiol)

Question 30

What are the four subdivided stages of the estrous cycle?

Answer 30

Follicular: Proestrus, estrus Luteal: Metestrus, diestrus

Question 31

What are the primary events in proestrus?

Answer 31

Formation of ovulatory follicle(s) and estradiol secretion

Question 32

What are the primary events in estrus (as a stage of the estrous cycle)?

Answer 32

Sexual receptivity and peak estradiol secretion

Question 33

What are the primary events in metestrus?

Answer 33

CL formation and beginning of progesterone secretion

Question 34

What are the main events of diestrus?

Answer 34

Sustained luteal secretion of progesterone

Question 35

Main characteristics of the estrous cycle of pigs?

Answer 35

Polyovular, polyestrous

Question 36

Main characteristics of the estrous cycle in mares?

Answer 36

Seasonally polyestrous in Spring. Signals start of the season via production of GnRH

Question 36

Main characteristics of the estrous cycle in bison?

Answer 36

Seasonal, unknown if polyestrous or monoestrous, in Autumn

Question 37

Main characteristics of estrous cycle in dogs?

Answer 37

Seasonally monoestrous (1-4 cycles per year in Spring)

Question 38

Main characteristics of estrous cycle in cats?

Answer 38

Seasonally polyestrous, induced ovulation

Question 39

What is "post-estrus"?

Answer 39

Describes the inter-estrus period that follows anovulatory estrus in induced ovulators (e.g. cats). Characterized by low E2 and P4

Question 40

What is lactational anestrus?

Answer 40

Period of anestrus while the dam is lactating to prevent pregnancy until the young are weaned

Question 41

How does follicle ablation work?

Answer 41

Ultrasound-guided transvaginal ablation of antral follicles induces emergence of a new follicular wave 1.5 days later because FSH is no longer inhibited

Question 42

What is superovulation?

Answer 42

A technique used to induce development of multiple follicles, leading to release of multiple oocytes in a single cycle

Question 43

When is it best to perform a superovulation procedure?

Answer 43

Prior to selection of a dominant follicle

Question 44

Why might induced ovulation be evolutionarily advantageous?

Answer 44

Species with marked population fluctuations, and solitary/nongregarious species

Question 45

What is the hormone present in camelid semen that is thought to be related to induced ovulation?

Answer 45

NGF (Nerve growth factor)

Question 46

What is the other hormone (other than NGF) that may be involved in induced ovulators?

Answer 46

Estradiol reaching a threshold to trigger spontaneous ovulation